Environmentalists observed the diminishing of and global warming trends.

"Seeds" trait most likely helped young angiosperms in this way.

Option: B

Explanation:

Angiosperm, the largest and most abundant group within the Plantae Kingdom, one of about 300,000 species of flowering plants. Angiosperms compose about 80 per cent of all now existing known green plants. In an enclosed hollow ovary grows into a seed as angio are vascular seed plants where the ovule or egg is fertilized. Generally, the ovary itself is wrapped in a flower, that portion of the angiosperm plant which comprises the both male or female reproductive organs.